The present invention relates to a method and a device for preventing the habituation of a fragrance composition.
It is generally known to use an electrical device to evaporate a perfume and/or fragrance composition into a space, particularly a domestic space, e.g., a living room, to provide a pleasant aroma. There are a variety of such devices on sale, for example the Airwick Diffuser Actif(copyright) (manufactured by Reckitt Benckiser) or the Ambi-Pur(copyright) fragrance diffuser (manufactured by Sara Lee). Generally, these devices consist of a perfume or fragrance source, an electrical heater and a power supply. By the application of heat to the perfume or fragrance source, there will be a constant supply of the perfume or fragrance to the space in which the device is placed.
The problem with this arrangement is that a person occupying the space will quickly become accustomed to the perfume or fragrance and, after a while, will not perceive the fragrance strength as being as intense. This is a well-known phenomenon called habituation. A solution to this problem has been sought.
According to a first aspect of the present invention there is provided a method for preventing the habituation of a fragrance composition, which method comprises providing to a space which it is desired to fragrance two or more fragrance compositions, at least one of which fragrance compositions is provided periodically. According to the invention there is further provided a method wherein a continuous supply of a first fragrance composition and a periodic supply of a second fragrance composition are provided to the space which it is desired to fragrance.
According to a second aspect of the present invention there is provided a device for supplying two or more fragrance compositions to a space which it is desired to fragrance, the device comprising a supply source for periodically supplying at least one of the fragrance compositions to the space. Preferably, the device further comprises a second supply source, which second supply source is adapted to continuously supply a first fragrance composition to the space which it is desired to fragrance.
Each fragrance composition is preferably in the form of a liquid. Suitable solvents for the fragrance components include water, alkyl alcohol, e.g., isopropanol or ethanol, an ether (such as monopropylene glycol methyl ether, dipropylene glycol methel ether and/or tripropylene glycol methyl ether), carbitol or a glycol (such as propyleneglycol or dipropyleneglycol).
When the fragrance composition is in the form of a liquid, it is generally supplied in (or its source is) a container, e.g., a bottle filled with the liquid and provided with a wick. A suitable container is one made from a water/organic solvent insoluble material, which is optionally either a plastic material, for example polypropylene, HDPE (high density polyethylene), PET or Barex or, preferably glass. Suitable wicks are made from natural or synthetic fibrous materials, such as cotton, fiberglass, mineral fibers, cellulose ceramic, graphite or polyester.
Each fragrance composition may additionally comprise a malodor counteractant and/or an insecticide. Preferably, it is the first fragrance composition which may further comprise a malodor counteractant and/or an insecticide.
A suitable fragrance composition for use in the invention comprises one or more fragrant components, such as cedarwood oil, sandalwood oil, bergamot, Bulgarian rose oil, patchouli, myrrh, clove leaf oil, linalol, ethyl alcohol, terpineol, menthol, citronellal, and/or phenyl ethyl alcohol.
The fragrance compositions are preferably chosen such that the two or more fragrance compositions contrast with one another or have different notes. This is particularly important when one fragrance composition is supplied continuously and one is supplied periodically to prevent cross habituation. This is a preferred feature because, if the second fragrance composition is too similar to the first fragrance composition, the periodic supply of the second fragrance composition will not act to counteract the effects of the habituation.
An advantage of the invention is that the problem of habituation is alleviated. In carrying out a preferred embodiment of the method of the invention, a continuous supply of a fragrance composition and a periodic supply of at least one further fragrance composition are supplied to a space which it is desired to fragrance. If the fragrance compositions were continuously supplied, and if there were no periodic supply of a fragrance composition, then a person present in the space would quickly become accustomed to the fragrance composition or compositions. In other words, the person would believe that the strength of the fragrance composition or compositions was decreasing with time. However, when at least one fragrance composition is periodically supplied, the perceived decrease in the strength of the fragrance composition which is continuously supplied is halted. In other words, with the continuous supply of a first fragrance and a pulsed supply of a second fragrance, the strength of the first fragrance is perceived as stronger than it was before the second fragrance composition was supplied.
A suitable deodorant for use in the present invention is one or more aroma and/or non-aroma chemicals, which are known to have an action in reducing the perception of the intensity of malodors, e.g., unsaturated esters, ketones, aldehydes, and/or a fragrant material, e.g., citronella and/or cedarwood oil (which is known to counteract the perception of tobacco malodor).
A suitable insecticide for use in the present invention comprises one or more natural insecticides, such as pyrethroid, nicotinoid, rotenoid and/or one or more synthetic insecticides, e.g., Tetramethrin(copyright), Bioallethrin(copyright), Allethrin(copyright), phenthrin, a dinitrophenol, an organothiocyanate, benzene hexachloride, a polychlorinated cyclic hydrocarbon (e.g., Heptachlor(copyright), Aldrin(copyright) and/or Telodrin(copyright), and/or an organophosphorous compound (e.g., tetraethyl pyrophosphate).
Each fragrance composition may further comprise an antioxidant, such as tocopherol, ascorbyl palmitate, butylated toluene, ascorbic acid, tert-butyl hydroquinone, beta carotene and/or a gallate. In addition each active agent may optionally comprise a UV stabilizer, such as Uvinol 400.
In carrying out a preferred embodiment of the present invention, a fragrance composition is generally pulsed from a device which includes a heater, which is adapted to supply heat periodically to the composition which is to be pulsed and thereby vaporize it. When two or more fragrance compositions are to be supplied periodically, the two or more compositions may be pulsed by the use of periodic heaters to the two compositions. Alternatively, if one fragrance composition is to be supplied continuously, then the heater will supply heat continuously to this composition to vaporize it continuously. The other fragrance composition will be heated only periodically to provide pulsed evaporation.
The heater is optionally either a positive temperature coefficient-type (PTC-type) electrical heater or a resistance-based electrical heater. It is preferably a PTC-type electrical heater. The heat output of the heater is preferably suitable to give an operating temperature of from 50 to 120xc2x0 C., more preferably from 60 to 80xc2x0 C., most preferably about 70xc2x0 C.
Each fragrance composition will generally be supplied in a container provided with a wick. The heater will then preferably be in the form of a coil or a ring around the wick. Preferably, the heater is provided with a control which regulates the supply of heat to the fragrance compositions. This is in order that the evaporation rate of the fragrance compositions may be controlled.
Alternatively, a combined fragrance composition may be supplied in a single container with a wick, with the fragrance which is to be pulsed having a higher vaporization temperature than the fragrance which is to be continuously released. Supply of heat to the wick will vaporize the first fragrance which is to be supplied continuously. The second fragrance may then be vaporized by periodically increasing the heat supply to the wick.
The device according to the second aspect of the present invention is preferably an electrical device. The electrical power supply is optionally either in the form of one or more electrical batteries or, preferably, the electrical device is adapted to be connected to an electrical power supply, e.g., a domestic mains socket. The device is preferably provided with an actuator, e.g. a switch, to control operation of the device.
The periodic supply of heat to release the fragrance composition is preferably achieved by providing the device and particularly the heater with a controller. The controller is preferably in the form of an electronic circuit, e.g. a printed circuit board. The controller is preferably an astable electronic timing circuit, for example one based on a 555 integrated circuit or an inverting Schmitt trigger (e.g. a 74LS14 integrated circuit). The controller is preferably arranged such that that a power supply is connected to the heater for a short period of time at a frequency of from 1 to 5 times an hour. This short period of time is preferably from 15 seconds, more preferably from 30 seconds to, preferably, 15 minutes, more preferably 2, 4, 6, 8, or 10 minutes, with appropriate intervals of time therebetween.